The invention relates generally to detecting turn faults in the stator of alternating current (AC) induction motors.
AC induction motors are used in a wide array of applications and processes. An AC induction motor typically includes a stationary portion, a “stator,” and a rotating portion, a “rotor.” In a 3-phase AC motor, power is applied to the stator to induce a magnetic field, causing the rotor to turn and generate mechanical energy. The stator may include any number of “windings,” or wound poles that carry the current necessary to induce the magnetic field. These windings may also be characterized by the “turns” in the windings.
In many environments, the windings in the stator are subject to shorts between the turns of the windings, commonly referred to as “turn faults.” Depending on the material used for the windings and the insulation, any number or types of failures may occur. Such failures may be mechanical, chemical, or electrical, and may result from degradation of the insulation, the winding material, a manufacturing defect, etc. These turn faults gradually result in extended failures of the windings and eventually result in failure, leading to replacement or repair of motor components or the motor itself. The repair or replacement of the motor or motor components may be unforeseeable and create undesirable downtime in the application or process using the motor when the motor is taken offline.